Obtaining and maintaining samples in the samples' native state from fluid environments can be difficult because of the environment of the fluid environment. Depending on the depth of interest or the chemistry of the fluid environment, these environments can vary starkly from the surface environment in terms of pressure and temperature. Some fluid environments possess extreme chemical characteristics, such as high acidity, high alkalinity or extreme anoxia. To fully understand and characterize fluids or microorganisms found in these liquid environments, a sampling apparatus must be able to obtain samples under varied environmental conditions, store said samples at substantial similar conditions as the ambient conditions of the retrieval site, and maintain said environmental conditions as sample is transferred from sampling apparatus.
Use of faulty sampling apparatuses unable to maintain the native environmental conditions of the fluid samples causes alterations of the physical and chemical nature of the fluid samples. Changes in temperature and pressure can cause the fluid samples to approach or reach saturation pressure causing gas stripping. Gas stripping occurs when gases and volatiles exsolve with increasing temperature and decreasing pressure. Bubble formation then leads to a loss of these gases. If the ambient conditions of the fluid sample's retrieval site are not maintained, the resultant changes in pressure, temperature or other environmental variants will result in alterations in the sample that render data analysis fruitless.
Berger et al., U.S. Pat. No. 5,806,186 disclose an apparatus and method for obtaining samples of formation fluid using a work string designed for performing other downhole work such as drilling, workover operations or re-entry operations. The apparatus includes sensors for sensing downhole conditions. The apparatus also includes a relatively small integral sample chamber coupled to multiple input and output valves for collecting and housing a formation fluid.
Taylor et al., U.S. Pat. No. 6,561,046, disclose an apparatus that allows multiple uncontaminated samples to be taken from hydrothermal vents and the oceanic or limnological water columns. The apparatus includes a sampling nozzle for taking in the sample and includes at least one sampling module for the collection of a predetermined type of sample. A fluid intake module is in fluid communication with the sample collection unit and the sampling nozzle. The fluid intake module includes at least one pump for drawing a sample through the sampling nozzle and sample collection unit. In operation the sampling nozzle is moved into a desired sampling location and a micro-controller sends a signal to the fluid intake module to initiate collection of a sample.
Armstrong et al., U.S. Pat. No. 4,660,423, disclose an apparatus for taking water samples from wells, streams, lakes or the like wherein the water sample is to be duplicative of the water that is being tested. The apparatus consists of a carrier adapted to be lowered on a line to any depth in to the water body to be sampled. The carrier is hollow and has an internal load carrying cavity in which a unit consisting of an isolation vial filled with distilled water and a sample collection vial which is evacuated and positioned within the isolation vial are loaded. Both vials are equipped with closing plugs therein which contain septums and a hollow needle structure is provided which pierces the isolation vial septum and extends into but does not pierce the sample collecting septum. In response to a jerk on the line, the carrier exerts a force on the needle unit which causes it to pierce the spectrum in the sample vial thereby communicating the interior of the sample vial with the water to be sampled, with the result that a sample of the water to be tested rushes into the sample vial.